Aspectos químicos, biológicos e etnofarmacológicos do gênero Cassia

Species of Cassia are widely distributed in tropical and subtropical regions throughout the world, and have been extensively investigated chemically and pharmacologically.They are known to be a rich source of phenolic derivatives, most of them with important biological and pharmacological properties. Some Asian, African and Indian tribes use these species as a laxative, purgative, antimicrobial, antipyretic, antiviral and anti-inflammatory agent. Among a number of other classes of secondary metabolites, such as anthracene derivatives, antraquinones, steroids and stilbenoids, biologically active piperidine alkaloids are an especially important bioactive class of compounds that showed to be restricted to a small group of Cassia species. In this paper we present an overview of the chemical, biological and ethnopharmacological data on Cassia piblished in the literature.

Interferentes endócrinos no ambiente

Although the hypothesis that environmental chemicals may exhibit endocrine disrupting effects is not new, the issue has been a growing level of concern due to reports of increased incidences of endocrine-related disease in humans, including declining male fertility, and more significantly, to adverse physiological effects observed in wildlife where cause and effect relationships are more evident. The list of endocrine disrupting chemicals (EDCs) includes a range of anthropogenic compounds, phytoestrogens, naturally occurring sex steroids and synthetic estrogens. Within the aquatic environment, the presence of EDCs has concerned many scientists and water quality regulators. Discharge of effluents from treatment facilities is likely to be a significant source of input of contaminants to many systems, and the potential for concentration of hydrophilic compounds and transformation products within sludges has implications for their disposal. Then, understanding the processes and the fate of EDCs on the environment, as well as the mechanisms of endocrine disruption, may facilitate controlling or limiting exposure of both humans and the environment to these compounds.

Constituintes químicos da ascídia didemnum psammatodes (sluiter, 1895) coletada na costa cearense

Chemical investigation of the methanolic extract of the ascidian Didemnum psammatodes has led to the identification of the nucleosides 2'-deoxyuridine (1), thymidine (2), 2'-deoxyinosine (3) and 2'-deoxyguanosine (4), the steroids cholestanol, cholestanone and stigmasterol in mixture and batyl alcohol plus two analogs, 1-heptadecyloxy-2,3-propanediol and 1-nonadecyloxy-2,3-propanediol in mixture. Their structures were proposed by NMR, MS and comparison with literature data and GC-MS analysis.

Constituintes químicos das cascas do caule de Cenostigma macrophyllum: ocorrência de colesterol

Phytochemical investigation of the bark of Cenostigma macrophyllum (Leguminosae-Caesapinioideae) resulted in the isolation and identification of valoneic acid dilactone, ellagic acid, lupeol, alkyl ferulate, four free sterols (cholesterol, campesterol, stigmasterol and sitosterol), a mixture of sitosteryl ester derivatives of fatty acids, sitosterol-3-O-beta-D-glucopyranoside, stigmasterol-3-O-beta-D-glucopyranoside and saturated and unsaturated fatty acids. The structures of the isolated compounds were identified by ¹H and 13C NMR spectral analysis and comparison with literature data. The mixtures of 3-beta-hydroxysterols and fatty acids were analysed by GC/MS.

Chemical constituents from Tabernaemontana catharinensis root bark: a brief NMR review of indole alkaloids and in vitro cytotoxicity

This work describes the isolation and structural determination of pharmacological compounds present in the bark of roots of Tabernaemontana catharinensis (Apocynaceae). Among the 27 substances detected 12 were identified as terpenoid-indole alkaloids, 2 steroids and 13 pentacyclic triterpenes. Structures were outlined based on HMQC, COSY, DEPT, 13C, and ¹H NMR data and MS. Spectral data of indole alkaloids were reviewed. An in vitro screening of the extracts and isolated compounds was carried out. Compounds ibogamine (5), 3-oxo-coronaridine (9) and 12-methoxy-4-methylvoachalotine (MMV) demonstrated effective cytotoxicity towards SKBR-3 breast adenocarcinoma and C-8161 human melanoma tumor cell lines.

Diterpenos casbanos e acetofenonas de Croton nepetaefolius (Euphorbiaceae)

Croton nepetaefolius is an aromatic plant native to the northeast of Brazil where it is extensively used in folk medicine as a sedative, orexigen and antispasmodic agent. The present work deals with the chromatographic analysis of the ethanolic extract of Croton nepetaefolius stalk. It allowed the isolation and characterization of two diterpenoids named 1,4-dihydroxy-2E,6E,12E-trien-5-one-casbane and 4-hydroxy-2E,6E,12E-5-one-casbane, two acetophenones named 2-hydroxy-4,6-dimethoxyacetophenone and 2-hydroxy-3,4,6-trimethoxyacetophenone and the steroids 3-O-b-D-glucopiranosylsitosterol and a mixture of b-sitosterol and stigmasterol. Structural elucidation was done on the basis of spectral data, mainly high field NMR and EIMS.

Constituintes químicos do caule de Senna reticulata Willd. (Leguminoseae): Chemical constituents isolated from the wood of Senna reticulata Willd.

The phytochemical investigation of the wood extracts of Senna reticulata (Leguminoseae) yielded six anthraquinones: chrysophanol, physcion, aloe-emodin, 1,3,8-trihydroxyanthraquinone, 3-methoxy-1,6,8-trihydroxyanthraquinone, emodin and the chrysophanol-10,10' bianthrone. The triterpenes a and b-amirin, the steroids b-sitosterol and stigmasterol as well as the flavonoid kaempferol were also identified. The structures were established by spectral analysis, including two-dimensional NMR techniques. It is the first report of 1,3,8-trihydroxyanthraquinone and 3-methoxy-1,6,8-trihydroxyanthraquinone in higher plants.

Alcalóides e outros metabólitos do caule e frutos de Zanthoxylum tingoassuiba A. St. Hil

Phytochemical investigation of this species, popularly known as tinguaciba and used in traditional medicine to various diseases, resulted in the isolation of 15 substances: 2 alkaloids - norchelerythrine and arnottianamide; 1 lignan - sesamin; 4 terpenoids - citronellyl acetate, lupeol, α-bisabolol and spatulenol; 5 coumarins described for the first time - xanthotoxin, isopimpinelin, O-prenylumbelliferone, imperatorin and aurapten, 1 protoalkaloid - methyl N-methylanthranilate and 2 steroids - stigmasterol and β-sitosterol. The structures of the compounds were elucidated by spectroscopic analyses and compared with literature data.

Estudo fitoquímico das cascas das raízes de Zanthoxylum rigidum Humb. & Bonpl. ex Willd (Rutaceae)

Chemical investigation from root barks of Z. rigidum, resulted in the isolation of lupeol, a mixture of steroids campesterol, sitosterol, stigmasterol, sacarose, hesperidin, N-methylatanine and 6-acetonyldihydrochelerythrine. Their structures were established by spectral data analysis. No previous work has been reported on Z. rigidum species.

Constituintes químicos de Sebastiania macrocarpa Muell. Arg. (Euphorbiaceae)

The chemical investigation of the methanolic extract of the aerial part of Sebastiania macrocarpa allowed the isolation of the mixture of steroids β-sitosterol and stigmasterol, gallic acid, and scopoletin. The hexane extract of the roots allowed the isolation of the triterpene lupeol and of the macrociclic diterpene (+)-tonantzitlolone. The structures of all compounds isolated were identified on the basis of their spectral data and by comparison of their spectral data with values described in the literature. This is the first report involving the chemical investigation of this species.

Constituintes químicos e atividade inseticida dos extratos de frutos de Trichilia elegans E T. catigua (Meliaceae)

Phytochemical investigation of the fruits extracts of Trichilia elegans and Trichilia catigua (Meliaceae) has led to the identification of the limonoids 11β-acetoxyobacunone, cedrelone, methylangolensate and epimeric mixture of photogedunin besides known coumarins (scoparone, scopoletin, umbeliferone) and the steroids stigmasterol, β-sitosterol, sitostenone and campesterol. The structures of the compounds were proposed by spectroscopic analysis and comparison with literature data. An evaluation of the insecticidal activity of the fruits extracts of Trichilia ssp. was carried out and the extracts of T. elegans revealed to have strong insecticidal activity and the extracts of T. catigua showed moderate larval mortality on Spodoptera frugiperda.

Esteroides produzidos por Penicillium herquei, um fungo endofítico isolado dos frutos de Melia azedarach (Meliaceae)

Six compounds comprising the groups of steroids, the ergosterol, the ergosterol peroxide, the cerevisterol, the neociclocitrinols, the ergosta-4,6,8(14),22-tetraen-3-one, the 25-hydroxy-ergosta-4,6,8(14),22-tetraen-3-one, were isolated from Penicillium herquei fungus obtained from Melia azedarach. The structures were identified by spectral methods of RMN 1D and 2D and MS.

Metabólitos secundários da família bromeliaceae

This review describes aspects of the Bromeliaceae family dealing the traditional applications, biological activities and distribution of secondary metabolites in distinct subfamilies. Some species are used with medicinal purposed in the treatment of respiratory, diabetes or inflammation diseases, and gastrointestinal disorders. Special emphasis on cycloartane triterpenoids and flavonoids, typical metabolites of this family, are presented. Bromeliaceae is unique amongst the monocotyledons in the frequency and variety of flavonoids with hydroxylation or methoxylation at the 6-position. Other compound classes as steroids, hidroxycinnamic acids, phenylpropane diglycerides, lignans, are presented.

Constituintes químicos do caule de Spathelia excelsa (rutaceae) e atividade frente a Aedes aegypti

Phytochemical investigation from the stems of Spathelia excelsa (Rutaceae) collected in Amazonas yielded deacetylspathelin (1), 7,8-dimethoxyflindersine (2), new glabretal-type triterpenoid 3β-angeloyl-21,24-epoxy-7α, 21α, 23α, 25-tetrahydroxy-4α, 4β, 8β, 10β-tetramethyl-25-dimethyl-14, 18-cyclo-5α, 13α, 14α, 17α-cholestane (3), in addition to the known steroids β-sitosterol and stigmasterol. Their structures were established on the basis of spectral data. The compounds 1 and 3 were assayed on Aedes aegypti (larvicidal and adulticidal activities and compound 3 exhibited larvicidal properties with LC50 of 4,8 µg/mL.

Estudo fitoquímico da madeira de Guarea macrophylla (Meliaceae)

In the present work, the crude ethanol extract from wood of G. macrophylla was submitted to liquid/liquid partition between hexane, CH2Cl2, EtOAc and n-BuOH. Each phase was individually chromatographed over silica gel, Sephadex LH-20 or Amberlite XAD-2 to give eight terpene derivatives, such as five sesquiterpenoids (caryophyllene oxide, guai-6-en-10β-ol, spathulenol, aromadendrane-4β,10α-diol and aloaromadendrane-4α,10β-diol) as well as three triterpenoids (cicloart-24-ene-3β,23(R*)-diol, cicloart-24-ene-3β,23(S*)-diol, and cicloart-23E-ene-3β,25-diol). Additionally, were isolated three fatty acids (linolenic, linoleic and stearic), two steroids (sitosterol and stigmasterol) and sacarose. The structures of all these compounds were characterized by spectrometric analysis, mainly mass spectrometry and NMR and comparison of these data described in the literature.